Two-way clutch



Aug. 2o, 1946.

TWO-WAY CLUTCH K. MILLERL 2,406,238

original Filed Dee. 8,'1941 Patented Aug. 20, 1946 TWO-WAY CLUTCH Kay Miller, Auburn, Ind., assigner to The Atwood Vacuum Machine Company, Rockford, Ill., a copartnership composed of Seth B. Atwood and James T. Atwood Original application December 8, 1941, Serial No.

422,045. Divided and this application Novem- `her `17, 1943, Serial No. 510,577

9 Claims.

This application is a division of my copending zltpplication Serial No. 422,945, filed December 8,

This invention rel-ates to friction-clutches and is more particularly concerned with a new and improved two-way clutch especially designed for use with a two-rate transmission in a tractor, tank, truck, or the like, but of course, is suitable for other uses.

The principal object of my invention is to provide a friction clutch of the kind mentioned, in which a pressure plate is arranged to cooperate selectively with either of two clutch disks, the one driving a shaft associated with .one gear train and the other driving a quill Vsurrounding the shaft and associated with the other gear train, whereby when the one diskvis engaged the other turns idly with its gear train, and vice versa, the purpose being lto, enable quick change in the drive ratio by merely Shifting the clutch instead of having to shift gears inthe transmission.

AAn important feature of .the present invention consists in the provision of spring means cooperating with clutch actuating levers so as to .apply spring pressure to the pressure plate in either direction, said spring means affording substantially constant pressure on the pressure plate in either position of clutch engagement and permitting movement past dead center position of the toggle linkage provided in certain forms for operating the actuating levers, whereby the clutch is automatically maintained in either engaged position under spring pressure until moved manually to neutral position orto the other engaged position. Y

lThe invention is illustrated in the accompanying drawing, in whichf Figure 1 is a longitudinal section through a two-way clutch made in accordance with my invention, half of the complete sectionbeing omitted to conserve space and permit showing the parts on a larger scale;

Fig. 2 is a sectional detail on the line 2 2 of Fig. 1, and

Fig. 3 is a diagrammatic illustration of the tworate transmission in connection with which the clutch of my invention is employed.

The same reference numerals are applied to corresponding parts throughout the views.

Referring first to Figs. l and 2, the reference numeral I designates the flywheel of an engine, and Il the back plate thereon. l2 is a driven shaft extending rearwardly from the iiywheel adapted for direct connection with the propeller shaft or to be extended into. the front end of the [ad gear box of a transmission, and I3 is a quill surrounding the shaft and serving as an auxiliary driven member, the shaft l2 being for high ratio drive` and the quill i3 for low ratio drive, as will soon appear. The shaft t? has the usual pilot bearing lil supporting the front end thereof at the center of the flywheel iii. l5 and I6 are clutch disks, the disk i5 having its center hub Il splined on the front end of the shaft i2 to transmit drive from the iiywheel to the shaft when the disk l5 is engaged, and the disk it having its hub i 3 splined on the front end of the quill I3 to transmit drive from the ywheel to the quill when the disk i5 is engaged. At I9 are shown the usual pads or facings on the clutch disks, and at 5t isV indicated a pressure plate between the two disks, adapted when moved forwardlyk t0 engage disk l5 with the driving face 22 on the back of the nywheel and the companion drivingvface 23 on the front of the pressure plate. The pressure plate is also movable rearwardly for engagement with disk le to cause engagement thereof with the driving face 2li on the back plate H and the companion driving face 25 on the back of the pressure plate, The pressure plate is suitably cast like the flywheel and back plate and the faces 22-25 are accurately machined on these cast parts to insure smooth clutch engagement. The back plate is suitably bolted to the flywheel by means of its marginal flange portion 25, as indicated at 2l. 40 is the throw-cut collar reciprocable relative to the quill i3 as by means of the anti-friction shifter ring lll. g The latter is usually provided with Vtrunnions for cooperation with a yoke, or other clutch operating means, not shown. Radial `notches 51 are provided in the periphery of the pressure plate to accommodate the headed inner ends 58 of plunger rods 59 which are slidably engaged in holes in plates 60 mounted on the pressure plate on studs @l and l62. The studs also support other plates 63 in spaced parallel relation to the plates 50, and the plungers v555 are slidably engaged in holes in those plates also. The plungers 59 carry coiled compression springs thereon between the plates 60 and 63, and the studs 6l and 62 carry other coiled compression springs (i5 and 65 thereon between the same plates. The plungers-59, of which there are preferably six for the clutch in equally circumferentially spaced'relation with respect to the back plate, each having associated therewith a pair of studs lil- 62 on the pressure plate, are fastened rigidly to a stamped `sheet metal -ring 01 disposed in concentric relation with the back plate and pressure plate, spacer sleeves 58 being provided on the plungers 5K9 between the plates t3 and ring 61 to provide space between the plates 63 and the ring 61 for the heads of the i studs ISI-62. The tightening'of the nuts 69 on the studs 6'I-62 and of the nuts 1.0 on the plungthe clutch is engaged under increased spring v pressure.

It should be clear from a study of Fig. 2 that when the ring 61 is moved in `either direction, that is toward or away from the fpresl a sure plate 56 for engagement of the disk 5,01" disk I6, the springs 64-,66 can be compressed to cause the pressure plate to engage the disk under increased pressure, the plates GU being moved to the right following engagement of the pres-l sure plate 56 with the disk I6 to further `compress the springs 64-66 so that the' disk is engaged under such increased pressure, and the plates 63 being moved to the left following engagement of the pressure plate 56 with the disk I5 so that the disk is engaged under the increased spring pressure. The ring v61 has hardened steel wear` segments 1I` welded, or otherwise suitably secured,

f on the opposite sides thereof for engagement by' ingers 12 provided onclutch actuating levers 13 and k1li.Y These levers are pivotally mounted on lugs 15fcast integral with and projecting rearwardly from the back plate II, and they have e on a Vspindle suitably mounted in spaced par-` toggle links 16v- 11 pivotally connected to theirI outer ends for connecting the levers `with-the throw-out collar 46, to which the other ends of v the toggle links are pivotally connected, as shown.

In operation, when the throw-out collar 46 is F moved forwardly, the levers 13 are operated to move the pressure plate 56 rearwardly to engage the disk I6 under heavy spring pressure as a v result of the further compressionV of the springs 64-66, in the manner previously described. The i links-16 are arranged to move past a dead center position, namely, past a point where thefpivots i 18 are in the same plane with the pivots'19 normal to the axis of rotation, the movement overcenter being limited in any suitable way, as by 1 engagement of the front end of the throw-out collar with a shoulder 80 on the sleeve 8I mounted on the back plate and supporting the throw-out collar. In that way the spring pressure is made effective to hold the throw-out collar 46 yieldingly in the extreme position so as to avoid likelihood of accidental disengagement ofthe clutch.

Thefact that the springs 64-66 are further compressed in the engagement of the clutch disk is,

however, principally of advantage from the standpoint that-it insures substantially constant spring l l' Here again the springs 64-66 are subjected to further-compression in therengagement of the clutch in a similar manner and for the same reasons previously mentioned, the links 11 being movable past `a dead center` positionwhere the pivots 82 are in the same plane with the pivots 83 `normal to the .axis of rotation. A split ring S on the rear end of the sleeve 8| limits the rearward movement'of the throw-out collar after the links'11'have been moved over center.

This clutch, as previously indicated, is used in speeds for forward and reverse drive.

i3, Which provides the low ratio drive, has a gear 5I Von the rear end thereof meshing with the conjunction with a two-rate transmission, where the shaft l2, as shown in Fig. 3, extends rearwardly from the clutch and has the rear end portion 50 either directly connected through a universal joint with the propeller shaft of the tractor, truck, tank, or other vehicle, or extended into the front end of the gear box of a change speed transmission providing any desired number of The quill larger gear 52 of a two-gear cluster, the smaller gear 53of which meshes with a large gear 54 on the shaft I2, whereby to drive the shaft I2 at a reduced speed when the disk I6 on the quill I3 is engaged. The cluster 52-53 is supported allel relation to the shaft I2 and quill I3; Oi course, when the disk I5 on the shaft IZ is engaged, the quill I3 and disk I6 are driven idly by reason ofthe reduction gearing connection with the shaft I2. Forward movement of the throwout collar 46 by means of a manually operable clutch pedal or lever (not shown) causes engagement of the disk I5. When the throw-out collar 46 is moved rearwardly by means of a manually operable clutch pedal or lever, the disk I6 is engaged. vThe springs 64-66, in addition to providing resilient engagement so that close adjustment is not required even though the clutch is of the over-center type, provide substantially constant pressure and accordingly non-slipping engagement regardless of the usual wear on the clutch facings I9. In addition the springs, as previously described, act to hold the throw-out collar 46 resiliently in either extreme position to avoid likelihood of accidental disengagement of the clutch.

It is believed the foregoing description conveys a good understanding of the objects and advantages of my invention. The appended claims have been drawn to cover all legitimate modications and adaptations.

I claim:

1. In a friction clutch, the combination with a flywheel constituting the driving element and a back plate in fixed axially spaced relation to the flywheel and turning therewith, of twov separate and independent clutch disks between the flywheel and back plate constituting the driven elements, a pressure plate between said disks turning with the flywheel and back plate and movable in either direction from a neutral position for driving engagement with either of said disks,

means driven by each of said clutch disks, a i' single ring in concentric relation to said plates and guided for limited axial movement ywith respect to the pressure plate, a plurality of coiled compression springs in circurlferentially spaced relation to said ring Vand plate and compressed therebetween in preloaded condition and arranged to apply increased spring pressure to the plate upon axial movement of the ring relative to the plate to either clutch engaging position, and posithe other arranged to engage the back plate, a

tive acting over-center means between the back plate and said ring to move the pressure plate in either direction relative to the back plate and further compress said springs so as to engage the clutch resiliently under increased spring pressure.

2. In a friction clutch, the combination of a flywheel constituting the driving element, a back plate for the ywheel, two separate and independent clutch disks .constituting the driven elements, vone arranged to engage the flywheel and pressure plate turning with the back plate and disposed between said disks to engage either disk selectively, means driven by each of said clutch disks, resilient means carried 'on the pressure plate and adapted to be stressed with respect to the pressure plate, positive acting over-center means for moving the pressure plate in either direction to engage the clutch, and a single intermediate ring for transmitting movement from the over-center means to said resilient means in either direction, whereby to stress said resilient means and accordingly engage the clutch resiliently in either direction.

3. In a friction clutch, the combination of a flywheel constituting the driving element, a back plate for the flywheel, two separate and independent clutch disks constituting the driven elements, one arranged to engage the flywheel and the other arranged to engage the back plate, a pressure plate turning with the backV plate and disposed between said disks to engage either disk selectively, means driven by each of said clutch disks, a cluster of springs carried on the back plate, said cluster including a plurality of coiled compression springs, a pair of plates between which said springs are caged, studs for supporting said cage plates on the pressure plate for sliding movement relative to the studs, a plunger extending through the cage plates and operatively associated therewith to move either of said plates toward the other upon movement of the plunger in one direction or the other, and clutch engaging means cooperating with Vthe aforesaid plunger for moving the pressure plate in either direction, whereby to engage the clutch resiliently in either direction.

4. A friction clutch as set forth in claim 3, wherein said clutch engaging means comprises a positive acting lever means, the clutch including a manually reciprocableV throw-out collar, toggle links connecting said throw-out collar to said positive acting lever means, and means for limiting movement of the throw-out collar in either direction so as to permit only a predetermined movement of said links past dea d center positions when the throw-out collar is moved to its opposite extreme positions.

5. In a friction clutch, the combination with a flywheel constituting the driving element and av back plate in xed axially spaced relation to the flywheel and turning therewith, of two separate and independent clutch disks between the flywheel and back plate constituting the driven elements, a pressure plate between said disks turning with the flywheel and back plate and movable in either direction from a neutral position for driving engagement with either of said disks, means driven by each of said clutch disks, a single ring in concentric relation to said plates and guided for limited axial movement with respect to the pressure plate, a plurality of coiled compression springs in circumferentially spaced relation to said ring and plate and compressed therebetween in preloaded condition and arranged to apply increased spring pressure to the plate upon axial movement of the ring relative to the plate to either clutch 'engaging position, and clutch engaging means cooperating with said ring to move the pressure plate in either direction relative to the back plate and further compress said springs so as to engage the clutch resiliently under increased spring pressure.

6. In a friction clutch, the combination of a flywheel constituting the driving element, a back plate for the flywheel, two separate and independent clutch disks constituting the driven ele'- ments, one arranged to engage the flywheel and the other arranged to engage the back-plate, a pressure plate turning with the back plate and disposed between said disks to engage either disk selectively, means driven by each of said clutch disks, resilient means carried on the pressure plate and adapted to be stressed with respect to the pressure plate, clutch' engaging means for moving the pressure plate in either direction, and a single intermediate ring for transmitting movement from the clutch engaging means to said resilient means in either direction, whereby to `stress said resilient means and accordingly engage the clutch resiliently in either direction.

7. In a friction clutch comprising a ywheel constituting the driving element, one or more clutch disks constituting the driven element, and a pressure plate for engaging the driving and driven elements, clutch actuating means comprising a single ring in concentric relation to said plate and guided for limited axial movement with respect thereto, a plurality of coiled compression springs in circumferentially spaced relation to said ring and plate and compressed therebetween in preloaded condition and arranged to apply increased spring pressure to the plate upon axial movement of the ring relative to the plate to clutch engaging position, and positive acting overcenter means between the backplate and said ring to move the pressure plate relative to the back plate and further compress said springs so as to engage the clutch resiliently under increased spring pressure.

8. In a friction clutch comprising a flywheel constituting the driving element, a back plate for the flywheel, one or more clutch disks constituting thevdriven element, and a pressure plate turning with the back plateV and arranged to cause engagement of'said driving and driven elements,

- clutch-actuating means comprising a cluster of vsprings carried on the pressure plate, said cluster including a plurality of coiled compression springs, a pair of plates between which said springs are caged, studs for supporting said cage plates on the pressure plate for sliding movement relative to the studs, and a plunger extending through the cage plates and operatively associated therewith to move either of said plates toward the other upon movement of the plunger in one direction or the other, and clutch engaging means cooperating with the aforesaid plunger for moving the pressure plate in either direction.

9. A clutch Ymechanism as set forth in claim 8, wherein said clutch engaging means comprises a positive acting lever means, the clutch including a manually reciprocable throw-out collar, toggle links connecting said throw-out collar to said positive acting lever means, and means for limiting movement of the throw-out collar in either direction so as to permit only a predetermined movement of said links past dead center positions when the throw-out collar is moved to its opposite extreme positions.l V

KAY MILLER. 

